Form Field Data Integrity - Preventing Wrong Characters

[random1]

I've looked through Javascript validation scripts but all the ones I've found cover validation upon submition.

 

I'm looking at entry point protect against wrong chracters.

 

E.g.

 

- Preventing all characters from being entered except numbers.

- Preveting all chracters except upper case and lower case letters

- Requiring that the chracters enter match a pattern (e.g. DD-MM-YYYY)

etc...

 

(Yes I have PHP code after to check all field data, I just want some nice front-end validation to filter out the bad entry straight up)

 

Any Ideas?

[random1]

I have found:

 

http://www.qodo.co.uk/blog/javascript-restrict-keyboard-character-input/

 

Source:

 

/* code from qodo.co.uk */
// create as many regular expressions here as you need:
var digitsOnly = /[1234567890]/g;
var floatOnly = /[0-9\.]/g;
var alphaOnly = /[A-Za-z]/g;

function restrictCharacters(myfield, e, restrictionType) {
if (!e) var e = window.event
if (e.keyCode) code = e.keyCode;
else if (e.which) code = e.which;
var character = String.fromCharCode(code);

// if they pressed esc... remove focus from field...
if (code==27) { this.blur(); return false; }

// ignore if they are press other keys
// strange because code: 39 is the down key AND ' key...
// and DEL also equals .
if (!e.ctrlKey && code!=9 && code!=8 && code!=36 && code!=37 && code!=38 && (code!=39 || (code==39 && character=="'")) && code!=40) {
	if (character.match(restrictionType)) {
		return true;
	} else {
		return false;
	}

}
}

 

That pretty much works as I need it but:

 

- It accepts invalid characters like % & * # and @